The wheat is first cleaned as thoroughly as possible to remove all
extraneous impurities. In the cleaning operations care should be taken
to scratch or abrade the bran as little as possible, for this reason:
The outer coating of the bran is hard and more or less friable. Wherever
it is scratched a portion is liable to become finely comminuted in the
subsequent reductions, so finely that it is impossible to separate it
from the flour by bolting, and consequently the grade of the latter is
lowered. The ultimate purpose of the miller being to separate the flour
portion of the berry from dirt, germ, and bran it is important that he
does not at any stage of the process get any dirt or fine bran speck or
dust mixed in with his flour, for if he does he cannot get rid of it
again. So it must be borne in mind that at all stages of flouring, any
abrasion or comminution of the bran is to be avoided as far as possible.

After the wheat is cleaned, it is by the first break or reduction split
or cut open, in order to liberate the germ and crease impurities. As
whatever of dirt is liberated by this break becomes mixed in with the
flour, it is desirable to keep the amount of the latter as small as
possible. Indeed, in all the reductions the object is to make as little
flour and as many middlings as possible, for the reason that the latter
can be purified, while the former cannot, at least by any means at
present in use. After the first break the cracked wheat goes to a
scalping reel covered with No. 22 wire cloth. The flour, middlings,
etc., go through the cloth, and the cracked wheat goes over the tail of
the reel to the second machine, which breaks it still finer. After this
break the flour and middlings are scalped out on a reel covered with
No. 22 wire cloth. The tailings go to the third machine, and are still
further reduced, then through a reel covered with No. 24 wire cloth. The
tailings go to the fourth machine, which makes them still finer, then
through a fourth scalping reel the same as the third. The tailings from